P0492: Secondary Air Injection System Insufficient Flow — Bank 2
What to do
Driveable with no symptom you would notice. Will fail an emissions test.
What this code means
Not enough injected air is reaching bank 2's exhaust — the counterpart of P0491. Both banks reporting insufficient flow together shifts suspicion back to the shared components: the pump, its relay, or the switching valve feeding both sides.
Likely causes
Start here
- Carbon-blocked secondary air passage · moderate
- Seized secondary air check valve · moderate
Less common
- Faulty secondary air switching valve · moderate
- Split or disconnected air hose · easy
- Failed secondary air injection pump · moderate
Symptoms
Components involved
Information, not instruction
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Community experience
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